- 1). Open "Exchange Server Administrator."
- 2). Click "Connections" in the left pane.
- 3). Click "Internet Mail Services" in the right pane.
- 4). Click the "Connections" tab, and then click the "Advanced" button.
- 5). Change the "Max No. of Inbound Connections," set by default to 30, to something higher. Microsoft recommends at least 100 for busy servers.
- 6). Click "Save." If you continue to experience the problem, set the "Max No. of Inbound Connections" even higher.
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